I have a White River 270, 9', 5wt fly rod that I broke 6" off of the tip. I retipped it at 8'6" and it cast a little stiff with the 5wt WF line. I over lined it with a 6wt line and it casts great. Is this a result of it losing 6" or would it have cast the 6wt better than the 5wt before it lost the 6"? It cast the 5wt great before it was broken. Thanks, flyrodder

There's a good chance that you may have liked that 5wt with a 6 line in the first place, even before you broke it

Fixing a broken tip isn't really that hard.
You find yourself a piece of scrap fiberglass rod that will fit tight on the inside of the two pieces, just like a spigot ferrule would.
Glue the three pieces together, wrap it with white rod building thread, and slap on a little finish.
Just like new